The present invention generally relates to the weaving art, and more specifically, relates to a new and improved construction of a so-called multiple longitudinal traversing shed weaving apparatus or loom, meaning a loom wherein a plurality of successive sheds are formed and retained to establish waves of sheds which travel longitudinally of the warp threads. Such type looms have also been referred to in the art as warp-wave looms, in order to distinguish the same from the type of loom using "weft waves" traveling transversely of the warp threads.
Generally speaking, the multiple longitudinal traversing shed weaving apparatus or loom of the present development is of the type comprising a weaving rotor which is provided with shed-retaining elements or members which retain the warp threads, throughout a predetermined path, in their upper shed position or lower shed position. Additionally, there is provided control means which, viewed in the direction of travel of the warp threads, is located forwardly of the weaving rotor and serves for the lateral deflection and allocation of each warp thread to a shed-retaining element which determines the upper shed or lower shed.
Multiple longitudinal traversing shed looms or warp-wave looms, as is known, form together with the so-called wave shed weaving machines, that species of multi-phase weaving machines or looms wherein there are continuously inserted a number of mutually stepwise shifted or staggered weft threads in likewise stepwise shifted and traveling sheds. While with the wave shed weaving machines or looms the sheds are simultaneously multiply formed over the width of the fabric and migrate in the weft direction, in the case of the multiple longitudinal traversing shed weaving looms there is formed, in each case, a shed over the entire fabric width and the successively formed sheds simultaneously move in the direction of the warp threads.
A first type of multiple longitudinal traversing shed weaving machine of the previously mentioned type has been proposed in U.S. Pat. No. 3,848,642 wherein the control means for the lateral deflection of the warp threads are constituted by rotatable control rolls which are provided at their outer surface with closed to-and-fro extending guide grooves positioned at an inclination with respect to the lengthwise axis of the control rolls and provided for each respective warp thread. During rotation of the control rolls the warp threads, in accordance with the course of the guide grooves, are laterally deflected, and thus, are allocated to the desired shed-retaining element. This allocation is augmented by separation elements which dip into the warp threads and are arranged, viewed in the direction of travel of the warp threads, directly after the control rolls.
With this multiple longitudinal traversing shed weaving machine a number of warp threads are allocated in each case with a single shed-retaining element. This leads to the result that the warp threads are relatively markedly deflected by the control rolls. The guiding of the warp threads in the guide grooves causes a pronounced loading of the warp threads, especially a pronounced friction between the warp threads and the guide grooves. Additionally, the control rolls are not variable and when changing over to a new fabric weave must be exchanged or at least restructured.